Wow....a long weekend finally has come to an end. I recently bought a 2001 XKR in need of some serious restoration, and have been throwing money at it (in a good way!). This poor car only has 60k miles on it, but the paint, tires, interior, windshield, engine,...you probably guessed....just everything needs to be replaced or gone through. I just finished replacing both my upper timing chain tensioners, as well as flushing the coolant and transmission. All things I feared beforehand. Here's how it went...

The upper timing chain tensioners are easy to replace, and thank goodness I did because they were already cracking! For anyone who has been dreading this job, if you can build a Lego set, I assure you, you can replace these tensioners. I was so nervous about accidentally screwing up the timing, that I had never thought I would do this job. Thankfully, the kit to lock the timing is only $100 and takes about 5 minutes to put on. I entered this job thinking I would do both tensioners and chains until the crankshaft pulley put a squash to those plans. The hood and fan housing had already been removed, so I took the opportunity to replace all the belts and bring the tensioners back to life. I was also able to drain the coolant from the radiator and do a partial flush. Soon we will make/buy/borrow the special tool to remove that pulley and do the bottom tensioners.
The torque wrench is my new best friend, and all the bolts including new spark plugs and coil packs were torqued exactly to spec. I grabbed a couple of continental belts off of eBay and checked the new water pump I put in for leaks. All good there. Me and a friend finished the timing chain extravaganza at 1 in the morning, then took the car out for a brief victory lap.

The next day came the transmission. It shifted hard and had probably never had the fluid replaced. I ordered all of the parts from FCP Euro (highly recommend!). This included the pan gasket, filter, dipstick tube, dipstick cap, dipstick locker, pan bolt washer, and sensor connector (commonly leaks). All genuine Mercedes parts- in total less than $100, and shipped immediately. I purchased Fuchs Titan ATF 4134 five quart and one quart from Amazon. The transmission fluid, liquid-moly, that FCP recommends was not on the safe list I was looking at, so I decided to buy the Fuchs separately. Simple as 1. Unbolt and drain the fluid into a 5-gal bucket (have cardboard on the floor in case of drips). 2. Remove the filter (have a bag close by as well as paper towels to clean the gasket area). 3. Install the new filter and place the clean pan back on. 4. Wiggle the sensor off, unscrew the bolt in the center of the connector and remove it, screw the new connector back in, and fit the sensor back on. 5. Pour the fluid from the bucket into a measuring container (ex. an empty 5-quart oil jug), and put the same amount of new fluid measured, back in. This can be achieved by removing the dipstick cap and using a funnel and/or hose to pour fluid back in. 6. Shift through drive, reverse, and neutral a couple of times while the car is on. You can measure by sticking the dipstick in and seeing where the fluid is according to the temperature. For good measure, I drove to a local transmission shop and he checked the level for free! The transmission is shifting much smoother and usually takes 400 miles to reprogram after putting in a new battery. TO NOTE- The transmission will not shift normally if the car is not running normally. I recently have been having some issues with the MAF, and that has been reflected in the shifting.

All in all a very productive three days. The car is in the shop getting a new windshield, and new tires are being put on Monday, followed by dent removal and paint. I still have to work on my interior (wood paneling and driver's seat), and send my ABS module to be rebuilt. Red stuff brake pads are coming in the mail and I'm hoping to get around to upgrading the bushings (to polyurethane) before I do a full brake job (rotors, paint, rebuilding calipers, braided line, etc.). Will continue updating as I go along!

 

Those are the original, all-plastic body tensioners. I'm guessing that your car must have been one of the last to be fitted with those monstrosities.

Richard

 

Let us know how the Dip stick works out. I'm assuming the dip stick is for transmission. If so do you have part#?

Jack

 

Check ebay or amazon for a Mercedes 722.6 dip stick.

 

try Pelican Parts.

they have many parts for the 722.6 transmission. Many are genuine Mercedes items

https://www.pelicanparts.com/More_In...1&bc=c&SVSVSI=

the trouble I’ve had with eBay is that many / most parts sold as genuine MB parts are substandard counterfeits.

And in my case, in the purchase of the solenoid plate / conductor plate which turned out to be a counterfeit, the counterfeits don’t work correctly (bad embedded trans temp sensor) and cause spurious false HIGH TRANS TEMP warnings. .

Very aggravating.

you can trust Pelican Parts to list the parts honestly and say whether they are genuine MB parts, or aftermarket.

Z

 

@RichardS Yes, unfortunately its a 2001, but produced a couple months before they changed the tensioners from the awful plastic ones. I don't understand who thought plastic timing chain tensioners were a good idea. Thankfully, I replaced them as they both were already cracking, and the coil on one was not operating as it should have.

@JACKP The dipstick I used is here. It's from FCP Euro, and if you search the 722.6 transmission, it will display all of the things you need to do a transmission flush. Cheaper than Pelican parts by a little bit, but also all genuine Mercedes parts for the Mercedes transmission we have on the XKR. The dipstick works fantastic, you just have to wiggle it and make sure it gets all the way in- but you also don't want it bending and going flat against the bottom. No need for hard pushing. Measure while the car is on, and drive it until it gets up to temperature to measure again. Because transmission oil expands, the dipstick has two markers for different temperature. (one at cold start temp, the other at running temp). I would recommend taking it to a transmission shop to make sure the fluid at the level it should be, it won't take them more than 5 minutes to measure it and ideally won't cost much, if anything.

 

According to forum posts by those more experienced than I, the ears on the bottom of the dipstick prevent it from ever bottoming out.

in using mine, it does take a considerable amount of twisting and pulling up then re-inserting while twisting to get to go all the way in.

I’d have to measure how much of the flexible dipstick is actually down the tube, I can’t recall off the top of my head.

Z

 

@zray the only reason I mentioned the stick bottoming out, is because that happened to me, and I didn't force it very hard at all. The transmission guy noted it looked like it had, which would explain why the first reading I got had oil on the whole stick. Turned out it was 2 quarts low!

 

Just passing on what has been posted previously:
that the ears on the plastic part of the dip stick are there to catch on the narrowed part of the tube, thereby preventing the dip stick from going any lower.

I’m not an authority on any aspect of these cars, other than being experienced in buying copious amounts of gasoline.

Z